package com.cqcet.wenchuang.filter;

import com.alibaba.fastjson.JSON;
import com.cqcet.wenchuang.common.BaseContext;
import com.cqcet.wenchuang.common.R;
import lombok.extern.slf4j.Slf4j;
import org.springframework.util.AntPathMatcher;

import javax.servlet.*;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

/*
 * 检查用户是否已经完成登录
 * */
@Slf4j
//@WebFilter(filterName = "loginCheckFilter", urlPatterns = {"/*"})
public class LoginCheckFilter implements Filter {
    //路劲匹配器，支持通配符
    public static final AntPathMatcher PATH_MATCHER = new AntPathMatcher();

    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
        //向下转型
        HttpServletRequest request = (HttpServletRequest) servletRequest;
        HttpServletResponse response = (HttpServletResponse) servletResponse;
        //1.获取本次请求的URI
        String requestURI = request.getRequestURI();

        log.info("过滤到的请求：{}", requestURI);

        //定义不需要处理的请求路径
        String[] urls = new String[] {
//                "/**",
                "/users/login",
                "/users/logout",
                "/admins/login",
                "/admins/logout",
                "/backend/**",
                "/swagger-ui/**",
        };
        //2.判断本次请求是否需要处理
        boolean check = check(urls, requestURI);
        //3.如果不需要处理，则直接放行
        if (check) {
            log.info("本次请求{}不需要处理", requestURI);
            filterChain.doFilter(request, response);
            return;
        }
        //4.判断登录状态，如果已登录，则直接放行
        if (request.getSession().getAttribute("user") != null) {
            log.info("用户id：{}", request.getSession().getAttribute("user"));

            //将当前用户id存入ThreadLocal中
            Long userId = (Long) request.getSession().getAttribute("user");
            BaseContext.setCurrentId(userId);

            filterChain.doFilter(request, response);
            return;
        }
        log.info("用户未登录");
        //5.如果未登录则返回未登录结果，通过输出流的方式来向客户端响应数据
        response.getWriter().write(JSON.toJSONString(R.error("NOTLOGIN")));
    }

    /**
     * 路径匹配，检查本次请求是否需要放行
     *
     * @param urls
     * @param requestURI
     * @return
     */
    public boolean check(String[] urls, String requestURI) {
        for (String url : urls) {
            if (PATH_MATCHER.match(url, requestURI)) {
                return true;
            }
        }
        return false;
    }
}
